WASHINGTON -- U.S. Navy video of five small Iranian boats having a weekend exchange with three U.S. warships in the Persian Gulf was denounced Wednesday by Iran as fake.

The Pentagon video shows five small blue boats Iran later confirmed were of Iran's Revolutionary Guard approaching the U.S. ships at high speed Sunday in the Strait of Hormuz.

Radio communication from the USS Hopper can be heard demanding the boats identify themselves and change course but for almost 30 minutes, the boats circled alongside the USS Ingraham, Voice of America reported.

The Navy said white boxes were thrown into the water but that couldn't be seen on the tape. About the time that the items were reportedly pitched into the water a voice can be heard on the radio saying "You will explode after two minutes."

Soon after the video's release, a member of the Navy Forces of the Revolution Guards Corps told Iran's Press TV the video footage had been compiled using archival pictures and the audio had been fabricated.